The American Cancer Society estimates that a total of 240,430 new breast cancers were diagnosed in 2007 (178,400 new cases of invasive breast cancer, and 62,030 new cases of in situ breast cancer). Approximately 180,000 of these patients undergo breast conserving surgery (BCS), also called lumpectomy. Multiple recent studies show that a staggering 20-70% of the 180,000 patients (45% or ~81,000 women on average) have to return for a repeat surgery due to incomplete removal of the cancer at the first BCS. The long-term objective of this research is the market introduction of a clinically useful, intra-operative device for breast tumor margin assessment. The objective of the proposed research is to develop a clinical-trial-ready device and to evaluate its practical utility as a routinely used intra-operative tool. The specific aims of the proposed work are: (1) to design, fabricate and characterize a multi-channel optical spectral imaging system that will provide two- dimensional measurements from a depth of up to 2 mm within breast tissues in order to detect close and positive tumor margins in freshly excised lumpectomy specimens, (2) to perform a verification study of the device design specifications on tissue phantoms and (3) to perform a critical evaluation of the device in a practical clinical setting. The proposed technology will be a multi-channel optical assay device for intraoperative imaging of margins in specimens excised from patients undergoing breast conserving surgery (partial mastectomy). It is theorized that this optical assay system will help guide the surgeon to either complete the surgery, when margins are negative, or re-excise additional tissue, when margins are positive. The proposed clinical study will serve as an important database for future technological developments related to effective intra-operative assessment of tumor margins in patients with breast cancer. Successful completion of the long-term objectives of this research will result in significant benefits to breast cancer patients (preventing tens of thousands of unnecessary surgeries each year) as well as surgeons, hospitals, and health-care providers. The technology proposed in this research could also potentially be utilized in the assessment of tumor margins in patients with other types of cancers, widening the potential health impact of the research. PUBLIC HEALTH RELEVANCE: The goal of this STTR proposal is to develop a non-invasive multi-channel optical assay device for intra-operative imaging of tumor margins in tissue specimens excised from patients undergoing breast conserving cancer surgery. The proposed research is significantly relevant to public health due to the potential to contribute to the reduction of tens of thousands of unnecessary breast re-excision surgeries each year, and the corresponding lowered risk of local recurrence in patients with invasive and non-invasive breast malignancies who have their cancer fully removed in the first surgery.